Adhesive applicator

ABSTRACT

ADHESIVE APPLICATOR FOR APPLYING A DOUBLE FACED PRESSURE SENSITIVE SHEET FROM AN ADHESIVE SUPPLY ROLL HAVING PAPER SEPARATING ADJACENT SHEETS WHERE THE APPLICATOR HAS A ROTATABLE SHAFT FOR SUPPORTING THE ROLL, A DRIVEN MANDREL ABOUT WHICH THE SEPARATING PAPER IS WOUND AS IT IS STRIPPED FROM THE ADHESIVE SHEET AND GEARING OPERATIVELY CONNECTING THE SHAFT AND MANDREL WHEREBY AS THE ADHESIVE SHEET IS PULLED FROM THE ROLL, THE SEPARATING PAPER IS STRIPPED FROM THE ADHESIVE AND WOUND ON THE MANDREL. A SEVERING DEVICE WHEREBY DOUBLE-FACED PRESSURE SENSITIVE ADHESIVE SHEET APPLIED TO AN ARTICLE MAY BE ACCURATELY CUT AND SEVERED FROM A SUPPLY ROLL OF THE ADHESIVE SHEET.

Jan. 19, 1971 R. 1'. aRAz oovlc 3,555,913

' ADHESIVE APPLICATOR Filed March 8, 1968 5 SheetsSheet 1 INVENTOR. ph T. Brozdovic Rudol Wm M ATTORNEYS 1971 R. T. BRAZDOVIC 3,556,913

ADHES IVE APPLI CATOR Filed March 8, 1968 3 Sheets-Sheet 2 INVENTOR.

BY flw, W, 140- 1 7 ATTORNEYS Rudolph I. Bruzdovic 1971 R. T. BRAZDOVIC ADHESIVE APPLICATOR 3 Sheets-Sheet 5 Filed March 8, 1968 .m V S R n m m 4, W N /R m m W m T WB NU TU A m m 0 d I u R, W Y a B 1 United States Patent 3,556,913 ADHESIVE APPLICATOR Rudolph T. Brazdovic, Pittstown, N.J., assignor to Wood Industries, Inc., Plainfield, N.J., a corporation of Virginia Filed Mar. 8, 1968, Ser. No. 711,739

Int. Cl. B32b US. Cl. 156-584 4 Claims ABSTRACT OF THE DISCLOSURE Adhesive applicator for applying a double faced pressure sensitive adhesive sheet from an adhesive supply roll having paper separating adjacent sheets where the applicator has a rotatable shaft for supporting the roll, a driven mandrel about which the separating paper is wound as it is stripped from the adhesive sheet and gearing operatively connecting the shaft and mandrel whereby as the adhesive sheet is pulled from the roll, the separating paper is stripped from the adhesive and Wound on the mandrel. A severing device whereby doub e-faced pressure sensitive adhesive sheet applied to an article may be accurately cut and severed from a supply roll of the adhesive sheet.

BACKGROUND OF THE INVENTION It is important in many instances when applying a two faced pressure sensitive adhesive sheet to an article that the adhesive sheet be applied evenly and smoothly without any wrinkles. This is particularly true where the ad hesive sheet is utilized to secure a thin light printing plate onto a saddle which in turn provides a means for securing the plate onto a rotatable printing cylinder of a printing press. It is necessary in such installations that thesurface of the adhesive after application to the surface of the saddle be free of any fingerprints, oil spots, dirt particles or wrinkles which could result in air entrapment between the adhesive sheet and surface of the saddle.

It is also important that the adhesive sheet applied to the saddle be trimmed after securing the plate to the saddle so that it will be the same size as the plate. If

there is an excess of adhesive sheet on the saddle surface which extends beyond the periphery of the plate after the plate is applied to the saddle, the excess sheet will then be able to pick up dirt or lint particles which could interfere with subsequent printing. If the adhesive sheet on the saddle is smaller than the plate so that portions of the plate are not secured to the saddle, the plate might then loosen on the saddle during a press run or dirt may become lodged between the plate and the saddle, either of which would adversely effect printing.

It is therefore an object of my invention to provide for an adhesive applicator by which a two-faced pressure sensitive adhesive sheet may be accurately applied to an article without the necessity of manually handling the adhesive sheet, and also to provide a means for winding a layer of separating paper used to separate adjacent layers of the adhesive sheet after the paper has been stripped from the adhesive sheet. It is a further object of my invention to provide for a severing means by which the adhesive sheet may be accurately severed from a supply roll and after it has been applied to an article.

SUMMARY OF THE INVENTION sheet is to be applied. The device includes a rotatable shaft which carries thereon a supply roll of double-faced pressure sensitive adhesive sheet wherein adjacent layers of sheet are separated 'by a paper backing. The device a so includes a driven mandrel about which the paper backing may be wound after it is stripped from the adhesive sheet. The mandrel and shaft are operatively connected by drive rollers one of which contacts the outer layer of paper backing on the supply roll of adhesive sheet and another of which contacts the outer periphery of the roll of paper backing on the mandrel such that rotation of the shaft drives the mandrel. Speed changing means are associated with the drive rollers such that the peripheral speed of the roller contacting the roll of backing paper being wound on the shaft is greater than that of the outer layer of adhesive sheet being unwound from the supply DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of an adhesive applicator constructed according to the invention as applied to a printing plate applicator;

FIG. 2 is a schematic view of a side of the appllcator illustrating the manner in which the double-faced adhesive sheet and backing paper are threaded through the applicator;

FIG. 3 is a side view of the applicator taken along lines IIIIII of FIG. 4;

FIG. 4 is a partial sectional view of the adhesive applicator illustrated in FIG. 1; and

FIG. 5 is a perspective view of a severing means for cutting the double-faced adhesive sheet after it has been applied to an article.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, there is illustrated an adhesive applicator 1 which is attached to a plate applicator 2 by which a thin flexible printing plate P may be attached to a rigid support saddle S whichin turn is adapted to be I the printing plate P may be accurately positioned by setting means 11 and 12. The table is mounted on slides 13 in order that it may be moved with respect to saddle S to bring the end of the plate P into the nip area between the saddle and roller 6 and so that the bottom surface of the plate may engage the adhesive surface on the saddle.

The adhesive applicator 1 which forms the subject of my invention comprises outer frames 15, only one of which is shown which are mounted in slides, also not shown, carried by the plate applicator 2 so that the adhesive applicator maybe moved by fluid motor 16 towards and away from the cylinder 5. The side frames 15 mount a rotatable plates 21 which pivot about shaft 22 as shown in FIG. 3.

As shown in FIG. 2, a sheet or layer of double-faced adhesive is withdrawn from roll 18 to pass over an adjustment roll 23 carried by the side frames 15. The adjustment roll has adjusting screw means 24 and 25 located at each end thereof in order that the roll may be adjustably skewed with respect to shaft 17 to assure that the sheet of adhesive withdrawn from the roll will be wrinkle free.

The adhesive sheet extends from the adjustment roll 23 upwardly to a nosepiece 26 which serves to guide and force the adhesive sheet into contact with the outer surface of a saddle S mounted on the cylinder 5. The nosepiece 26 is supported by the outer side frames and has a strip 27 on the end thereof made of a soft pliable material thereon which serves to press the sheet 19 firmly onto the outer surface of the saddle. The force which the strip 27 bears against sheet 19 is determined by fluid motor 16 and is such that it will smoothly press the adhesive sheet onto the surface of the saddle while at the same time forcing out any air bubbles that may be entrapped between the sheet and saddle.

The paper backing is stripped from the sheet 19 at the point where it is applied to the saddle and is threaded through nipping rolls 28 and 29 which are journalled in the inner side frames 21. The backing paper then passes over a guide roll 30 also journalled in the side frames 21 and then onto a mandrel 31 which is rotatably mounted by shaft ends 31' slidable in slots 32 in the frames 21 where the paper is wound into a roll 33. Mounting the mandrel in this manner allows it to move vertically in the slots as shown in FIGS. 2 and 3 in order to accommodate the increase in diameter of the roll 33 as the backing paper is wound onto the mandrel.

The inner side frames 21, rolls 28, 29 and 30, the mandrel 31 and roll of backing paper wound thereon are supported and restrained from pivoting about the shaft 22 by a drive roll 35 which bears on the outer surface of the roll 18. The cover of the roll 35 has a roughened surface in order that there will be a nonslip drive between it and the paper backing comprising the outer periphery of the adhesive roll. Roll 35 in turn has a gear 36 on the end thereof as shown in FIGS. 3 and 4 which meshes with a gear 37 connected to a shaft on which the nipping roll 29 is mounted. The gear ratio between gears 36 and 37 is such that the peripheral speed of the nipping roll 29 is greater than the peripheral speed of the tape being unwound from the roll 18. This assures that there will be tension maintained in the paper backing 20 to provide the force necessary to strip the backing from the adhesive sheet.

A gear 38 also on the same shaft as gear 37 meshes with a gear 39 positioned on the end of a shaft 40 upon which a roll 41 is mounted and which contacts the outer periphery of the paper backing being wound on the mandrel 31. The gear ratio between gears 38 and 39 is such that the peripheral speed of the surface of the roll 41 is greater than the peripheral speed of the adhesive sheet being unwound from roll 18. This further assures that the tension of the paper backing being wound onto the mandrel will be high thus resulting in the paper being wound in a tightly Wound roll.

Tension in the backing paper as it is being stripped from the adhesive sheet is varied by varying the nipping pressure between rolls 28 and 29. Nipping pressure between these rolls is maintained by springs 42 which connect the ends of the shaft 28' of the roll 28 to fixed posts 43 on the side frames 21. Nipping pressure may then be varied by varying the strength of the spring.

Over-all tension of the backing paper being wound onto the mandrel 33 is varied by regulating a drag brake 50 mounted on one end of the shaft 17 as shown in FIG. 4. Drag brake 50 comprises a friction disc 51 which bears on the end of shaft 17 upon which the roll of double-faced adhesive sheet is mounted. Pressure between the disc and the end of the shaft 17 is varied by means of a screw 52. The braking means 50 is mounted in one of the outer side frames 15 by housing 53 which carries a bearing support member 54 and which is held in the housing by a nut 55. Bearing support member 54 in turn carries bearings 56 and 57 which rotatably support one end of the shaft 17. The roll 18 is held onto the shaft 17 by chucks 58 and 59 which engage the core 18 about which the sheet is wound. Sidewise adjustment of the roll with respect to the adhesive applicator is accomplished by turning screw 52. In some instances it may be necessary in order to maintain accurate side registry of the sheet on the saddle to move the core 18' sideways with respect to the saddle to compensate for discrepancies in the adhesive roll diameter or size variations of the core. This also may be done by regulation screw 52.

Referring to FIG. 5, there is illustrated a cutting device by which the double-faced adhesive strip may be cut without cutting the paper backing. It is important that the adhesive strip be smoothly out along a straight line to assure the strip will be prepared for the following saddle, and also to insure that sufficient strip is provided so there Will not be any portions between the saddle and plate which will not be contacted by the adhesive. As shown in FIG. 5, I have provided a cutting means 60 which may move transversely across the width of the adhesive layer such that a cutting tool 61 will cut the adhesive strip smoothly along a straight line. As shown, the cutting tool 61 is rotatably mounted in a carrier 62 which is slidable transversely across the adhesive backing along a track 63. Track 63 is mounted on rods 64, only one of which is shown, which are secured to the outer frames 15 so that the cutting wheel may be positioned at a set distance away from the cylinder 5 on which the saddle is mounted when the applicator is moved towards the cylinder by fluid motor 16. A locking screw 65 is provided for locking track 63 into place.

The cutting means 60 is further provided with a Teflon strip 66 which holds one end of the adhesive sheet to the cutter after it has been severed from the sheet applied to the saddle. Teflon is used since its physical characteristics are such that it does not adhere to the double-faced adhesive as strongly as the adhesive adheres to the saddle such that when the adhesive sheet is brought into initial contact with the surface of a saddle, it will adhere to the saddle. Thus it is seen that the Teflon strip merely serves to hold the adhesive sheet in position between applications.

The application of a double-faced adhesive using the applicator as shown in the drawings comprises a minimum of steps. A roll of adhesive sheet is initially loaded into the shaft 17 and an end of the sheet is passed over the roll 23 and around the nose 26. A portion of the paper backing is then stripped from the tape and threaded through the rolls 28 and 29, over the roll 30 and onto the mandrel 31. Excess adhesive sheet from which the paper backing used to thread the applicator is stripped is then cut and discarded. Any adjustment that may be necessary is then made to roil 23 to compensate for uneven rolls of adhesive sheet to assure that the sheet passing over the nosepiece will be wrinkle free. The proper amount of tension is set into the system by adjustment of the screw 52 of the brake means.

When the adhesive sheet is to be applied to a saddle using the applicator of FIG. 1, fluid motor 16 is actuated to move the adhesive applicator towards the cylinder on which the saddle is mounted until the double-faced adhesive extending over the nosepiece contacts the surface of the saddle. The cylinder carrying the saddle is then rotated until an amount of adhesive sheet equal to the circumferential length of the plate is applied to the surface of the saddle. As the cylinder carrying the saddle is rotated, it pulls adhesive sheet from the roll 18 which in turn drives roll 35 thus driving the roll of paper backing being wound onto the mandrel 31 and automatically stripping the backing from the adhesive sheet. The cutting tool and carriage 62 is then moved across the sheet to cut the adhesive sheet from the sheet that has been affixed to the saddle. The applicator is then moved away from the saddle after which the saddle is ready to receive a plate.

It is seen that an adhesive applicator constructed according to my invention will apply a double-faced pressure sensitive adhesive sheet to the surface of a saddle firmly smoothly and without air bubbles and that the adhesive sheet may be cut and handled without actually touching it thus eliminating objectionable fingerprints. While I have described in detail a preferred embodiment of my invention as shown applied to a printing plate applicator, it is obvious that the adhesive applicator could be used to apply double-faced pressure sensitive adhesive to a variety of objects having either fiat or curved surfaces. As for example, the adhesive applicator could be used with a laminating device Where two or more materials are to be laminated together.

I claim:

1. An adhesive applicator for applying a double-faced pressure-sensitive adhesive sheet to an article from a supply roll where the sheet has on one side thereof a paper backing to separate adjacent layers of sheet when in roll form; said applicator comprising a rotatable shaft for carrying a supply roll of said adhesive sheet, a rotatable mandrel about which the paper backing stripped from said adhesive sheet is wound, a drive roll contacting the outer periphery of said supply roll, a driven roll engaging the outer periphery of paper backing wound on said mandrel, means operatively connecting said drive roll and said driven roll, and speed changing means associated with said means operatively connecting said drive roll and driven roll whereby the peripheral speed of the paper backing when being wound on said mandrel tends to be in excess of the peripheral speed of the adhesive sheet being unwound from said supply roll in order to impart tension in the paper backing being wound on the mandrel.

2. An applicator according to claim 1 having in addition placement means for moving said applicator relatively towards and away from the point of application of said adhesive sheet to said article.

3. An applicator according to claim 1 having in addition article moving means by which said article upon which said adhesive sheet is to be applied may be moved relative to said applicator whereby the adhesive sheet will be removed from said supply roll causing it and the shaft to rotate and to drive said mandrel.

4. An adhesive applicator according to claim 1 having in addition a severing cutter moveable in a transverse direction across the adhesive sheet and adjacent the point where the adhesive sheet is applied to said article whereby the adhesive sheet applied to said article may be severed from the supply roll.

References Cited UNITED STATES PATENTS 2,743,064 4/1956 Le Febvre et a1 l56-344 2,909,301 10/1959 Fritzinger 156-584 3,136,462 6/1964 Knutson 156-527 FOREIGN PATENTS 1,086,261 10/1967 Great Britain 156-584 SAMUEL FEINBERG, Primary Examiner US. Cl. X.R. 225-24 

